Cardiac valve procedure methods and devices

ABSTRACT

The present invention discloses devices and methods for performing intravascular procedures with out cardiac bypass. The devices include various embodiments of temporary filter devices, temporary valves, and prosthetic valves. The temporary filter devices have one or more cannulae which provide access for surgical tools for effecting repair of the cardiac valves. A cannula may have filters of various configurations encircling the distal region of the cannula, which prevent embolitic material from entering the coronary arteries and aorta. The temporary valve devices may also have one or more cannulae which guide the insertion of the valve into the aorta. The valve devices expand in the aorta to occupy the entire flow path of the vessel. In one embodiment, the temporary valve is a disc of flexible, porous, material that acts to filter blood passing therethrough. A set of valve leaflets extend peripherally from the disc. These leaflets can alternately collapse to prevent blood flow through the valve and extend to permit flow. The prosthetic valves include valve fixation devices which secure the prosthetic valve to the wall of the vessel. In one embodiment, the prosthetic valves have at least one substantially rigid strut, at least two expandable fixation rings located about the circumference of the base of the apex of the valve, and one or more commissures and leaflets. The prosthetic valves are introduced into the vascular system a compressed state, advanced to the site of implantation, expanded and secured to the vessel wall.

BACKGROUND

Of all valvular heart lesions, aortic stenosis carries the worstprognosis. Within one year of diagnosis, half of patients with criticalaortic stenosis have died, and by three years this figure rises to 80%.Currently, there is only one effective treatment for patients withaortic stenosis—aortic valve replacement via open heart surgery.Unfortunately, this is a substantial and invasive undertaking for thepatient.

While there have been significant advances in heart valve technologyover the last thirty years, there has been little progress in thedevelopment of safer and less invasive valve delivery systems. Aorticvalve replacement currently requires a sternotomy or thoracotomy, use ofcardiopulmonary bypass to arrest the heart and lungs, and a largeincision on the aorta. The native valve is resected through thisincision and a prosthetic valve is sutured to the inner surface of theaorta with a multitude of sutures passing into the wall of the aorta.This procedure is accompanied by a 5% mortality rate, in addition tosignificant morbidity (stroke, bleeding, myocardial infarction,respiratory insufficiency, wound infection) related to the use ofcardiopulmonary bypass and the approach to the aortic valve. Elderlypatients and those who require concomitant coronary artery bypassgrafting experience increased morbidity and mortality. All patientsrequire 4 to 6 weeks to recover from the procedure.

Less invasive approaches to aortic valve surgery have followed twopaths. In the Eighties, there was a flurry of interest in percutaneousballoon valvotomy. In this procedure, a cardiologist introducedcatheters through the femoral artery to dilate the patient's aorticvalve, thereby relieving the stenosis. Using the technology available atthat time, success was limited. The valve area was increased onlyminimally, and nearly all patients had restenosis within one year. Morerecently, surgeons have approached the aortic valve via smaller chestwall incisions. These approaches still require cardiopulmonary bypassand cardiac arrest, which entail significant morbidity and a prolongedpostoperative recovery.

A truly minimally invasive approach to the treatment of aortic valvedisease requires aortic valve replacement without cardiopulmonarybypass. Such an approach would reduce patient morbidity and mortalityand hasten recovery. Although there has been great progress in thetreatment of coronary artery disease without cardiopulmonary bypass(angioplasty/stenting and “off-pump” coronary artery bypass grafting),similar advances have not yet been realized in heart valve surgery. Withan aging population and improved access to advanced diagnostic testing,the incidence of aortic stenosis will continue to increase. Thedevelopment of a system for “off-pump” aortic valve replacement would beof tremendous benefit to this increasing patient population.

There are three significant challenges to replacing a diseased aorticvalve without cardiopulmonary bypass. The first is to remove the valvewithout causing stroke or other ischemic events that might result fromparticulate material liberated while manipulating the valve. The secondis to prevent cardiac failure during removal of the valve. The aorticvalve serves an important function even when diseased. When the valvebecomes acutely and severely incompetent during removal, the patientdevelops heart failure leading to death unless the function of the valveis taken over by another means. The third challenge is placing aprosthetic valve into the vascular system and affixing it to the wall ofthe aorta.

Temporary valves have been reported in the art, most notably by Boretos,et. al. in U.S. Pat. No. 4,056,854 and Moulopoulos in U.S. Pat. No.3,671,979. All temporary valves disclosed to date have been insertedinto a vessel, advanced to a location distant from the insertion siteand then expanded radially from the center of the vessel.

These designs have many disadvantages. First, they tend to occupy asignificant length of the vessel when deployed. During a valveprocedure, it may be advantageous to place the temporary valve in avessel between two branches leading from that vessel. It may also benecessary to insert other tools through the vessel wall between thosetwo branches. A temporary valve such as the ones disclosed in the artmay leave very little room between the branches for insertion of thesetools. The valves disclosed to date tend also to be rather flimsy andmay have difficulty supporting the fluid pressures while the valve isclosed. A more significant disadvantage of these valves is that theygenerally must be inserted into a vessel at a significant distance fromthe valve to allow adequate room for deployment. If some portions of theoperation are performed through the chest wall, insertion of such atemporary valve may require a separate incision distant from the chestcavity. This adds morbidity and complexity to the procedure. Anotherdrawback of the prior art is that valves with three or fewer leafletsrely on the perfect performance of each of those leaflets. If one of theleaflets malfunctions, the valve fails to function adequately.

Throughout this disclosure the terms proximal and distal will be used todescribe locations within the vascular anatomy. In the arterial system,proximal means toward the heart while distal means away from the heart.In the venous system, proximal means away from the heart while distalmeans toward the heart. In both the arterial and venous systems a distalpoint in a blood flowpath is downstream from a proximal point. The termsantegrade and retrograde flow are also used. In the arterial system,antegrade refers to flow away from the heart while retrograde refers toflow toward the heart. In the venous system, these terms are againreversed. Antegrade means toward the heart while retrograde means awayfrom the heart.

SUMMARY OF THE INVENTION

The present invention relates to devices and methods for providing avalve within a fluid-bearing vessel within the body of a human. Thepresent invention further relates to intravascular filters capable offiltering particulate debris flowing within a vessel. The presentinvention further relates to devices and methods for performing therepair or replacement of cardiac valves.

One aspect of the present invention involves methods and devices ofperforming aortic valve repair or replacement. In one form, the methodinvolves the steps of inserting at least a temporary valve and atemporary filter into a segment of the aorta. Following placement ofthese devices, various procedures can be carried out on the aorticvalve. Following the procedure, the temporary valve and temporarilyfilter can be removed.

The temporary valve acts to restrict retrograde blood flow whileallowing antegrade flow. Generally, the valve allows forward orantegrade flow during the systolic phase of cardiac rhythm whileobstructing flow during the diastolic phase. The valve serves to assistor replace the function of the native aortic valve while a procedure isperformed on the native valve. The temporary valve means can be one of avariety of possible designs. The embodiments described below are merelyillustrative examples and do not serve to limit the scope of thisinvention.

The temporary valve can be placed in any suitable location within theaorta and can be inserted either directly into the aorta itself oradvanced into the aorta from a peripheral vessel such as the femoral oraxillary artery. The temporary valve is preferably inserted into thevascular system in a compressed state requiring a relatively smallinsertion hole and expands or is expanded within the aorta at a desiredsite. It can then be compressed for removal. In its expanded state, thevalve can occupy the entirety of the aorta's flow path, although this isnot a requirement of the present invention and may not be preferred incertain patients with extensive atherosclerotic disease in the aorta.The temporary valve, therefore, can, but does not need to contact thewall of the aorta and can act to obstruct all or only a portion of theaorta's flow path.

The temporary filter acts to prevent emboli that may be dislodged duringthe valve procedure from moving distal to the filter. In a preferredmethod of use, the filter is placed in the aorta proximal to thebraciolcephalic artery to prevent emboli from reaching the brain. Thefilter can be one of a variety of designs, including, but not limited toa mesh filter with a pore size smaller than the dimensions ofanticipated embolic particles. The filter can be inserted directly intothe aorta or advanced into the aorta from a peripheral artery. It ispreferably inserted in a compressed state and expands or is expanded toa larger state at a desired site within the aorta.

The temporary filter and temporary valve can be separate elements orpart of a single device. They may be affixed to various tubes, rods,wires, catheters, etc., to aid in their insertion into and removal fromthe vascular system.

Once the temporary valve and filter have been placed within the aorta,various procedures can be performed safely on the aortic valve while theheart is beating. This includes, but is not limited to, balloon aorticvalvuloplasty, or removal of the aortic valve, followed by placement ofa permanent valve prosthesis. The temporary valve, temporary filter, orboth may be designed with lumens through which various procedureinstruments can be placed. Instruments might also be passed around thesedevices or through a site in the aorta proximal to them.

Another aspect of the present invention is a method of performing aprocedure on a beating heart involving, at a minimum, inserting into theaorta, a temporary valve, as described above, removing at least someportion of the native aortic valve, and placing a permanent valveprosthesis at a site within the aorta. The temporary valve allowsremoval of the native valve while reducing the risk of heart failure dueto insufficiency of the native valve. Removal of at least some portionof the native valve can be carried out with one or a variety of toolsthat can be inserted either directly into the aorta or through aperipheral artery and advanced to the native valve. Similarly, thepermanent valve prosthesis can be inserted either directly into theaorta or advanced into the aorta from a peripheral artery. The valveprosthesis is preferably inserted in a compressed state and expands oris expanded at the desired implantation site. The implantation site ispreferably proximal to the coronary arteries, but can be at any suitablelocation in the aorta. The valve can be one of a variety of types knownin the art, but is preferably a flexible valve suitable for insertinginto an artery in a compressed state. This method can further involvethe placement of a temporary filter as described above to reduce therisk of emboli generated during manipulation of the native valve. Asdescribed above, the temporary filter can be a separate device or anintegral component of the temporary valve.

Any procedure performed using the disclosed methods can be assisted byone of a variety of visualization technologies, including, but notlimited to, fluoroscopy, angioscopy and/or epi-cardial, epi-aortic,and/or trans-esophageal echocardiography. These methodologies allowreal-time visualization of intra-aortic and intra-cardiac structures andinstruments.

Specific reference is made to procedures performed on the aortic valvein this description, however the methods and devices described hereincould be applied to other valves within the heart. The devices describedabove and in the claims below can be used as part of proceduresperformed on cardiac valves, but their use is not restricted to thislimited application.

DESCRIPTION OF THE DRAWING

For a fuller understanding of the nature and objects of the presentinvention, reference should be made to the: following detaileddescription taken in connection with the accompanying drawings, inwhich:

FIGS. 1A-1F depict various phases in the deployment of an exemplaryfilter device of the present invention;

FIGS. 2A-2C depict another embodiment of a temporary filter device. Asmall balloon located about the exterior of the cannula of this deviceforces blood to flow through a filter when inflated;

FIG. 3A shows a schematic representation of an endovascular procedurecatheter of the invention, with the one-way valve and filter membrane ina retracted position;

FIG. 3B depicts the endovascular procedure catheter of FIG. 3A followingdeployment of the one-way valve and filter membrane;

FIG. 4A depicts valve and filter components of the procedure catheter ofFIG. 3A viewed along the retrograde flow path. The valve is closed onthe left portion of FIG. 4A, preventing retrograde flow, and open on theright portion of FIG. 4A, allowing antegrade flow;

FIG. 4B depicts the “valve open” (left portion) and “valve closed”(right portion) positions of the procedure catheter of FIG. 3A viewedalong an axis perpendicular to the flow path;

FIG. 3A depicts the filter membrane element of the procedure catheter ofFIG. 1A as viewed along the flow path within a vessel;

FIG. 5B depicts the procedure catheter of FIG. 3A with the one-way valveremoved;

FIG. 6 depicts an exemplary deployment system for the temporary valveand filter elements of the endovascular procedure catheter of FIG. 3A;

FIGS. 7A-7D depict exemplary elements used to aid in deployment of thetemporary valve and filter element of the endovascular procedurecatheter of FIG. 3A;

FIGS. 8A and 8B depict another embodiment of a temporary valve andfilter device of the invention. The temporary valve of the depicteddevice is a small balloon on the outside of an inner cannula. Theballoon is inflated to prevent retrograde flow and deflated to allowantegrade flow;

FIGS. 9A and 9B depict another embodiment of a temporary valve andfilter device in accordance with the invention. Flaps of materialcollapse against the expandable mesh of the temporary filter to preventretrograde flow;

FIGS. 10A and 10B depict another embodiment of a temporary valve andfilter device in accordance with the invention. Slits cut in a valvematerial located about the expandable mesh provide a path for bloodduring antegrade flow and close against the expandable mesh duringretrograde flow;

FIGS. 11A and 11B depict the device of FIGS. 2A-C with the addition of aone-way valve;

FIG. 12 depicts an exploded cross-sectional view of an alternativetemporary valve assembly in accordance with the invention. In FIG. 12,components of the valve pieces are shown in cross section except forbacking element 110 and valve 111;

FIGS. 13A, 13B, 13C, 13C, 13D and 13D depict a series of cross-sectionalviews of the valve assembly illustrated in FIG. 12;

FIG. 13A depicts the valve of the exemplary valve assembly of FIG. 12 ina compressed state within a delivery cannula 105;

FIG. 13B depicts the valve of FIG. 13A advanced outside of deliverycannula 105;

FIG. 13C depicts the expanded valve of FIG. 13A seen looking down thelong axis of the vessel into which it is deployed. The valve is expandedby pulling back on button 101. In FIG. 13C, the valve is open, allowingflow through flexible loop 109. This depiction represents the state ofthe valve during the systolic phase when placed in the aorta and actingto support the aortic valve;

FIG. 13C is the same as FIG. 13C with the valve assembly viewed along aradius/diameter of the vessel into which it is deployed. Valve leaflets111 extend away to the right (as shown) of flexible loop 109;

FIG. 13D depicts the expanded valve of FIG. 13A seen looking down thelong axis of the vessel into which it is deployed. In FIG. 13D, thevalve is in a closed position, preventing flow through flexible loop109. This depiction represents the state of the valve during thediastolic phase when placed in the aorta and acting to support theaortic valve;

FIG. 13D′ is the same as FIG. 13D with the valve assembly viewed along aradius/diameter of the vessel into which it is deployed. Valve leaflets111 are collapsed against backing 110;

FIGS. 14A-14D depict the valve end of temporary valve assembly of FIG.12 inserted into a vessel. FIG. 14A is a lateral view, showing partialdeployment into the vessel. FIG. 14B is a lateral view of the deploymentof FIG. 14A, showing a rod 106 positioning the temporary valve into thevessel. In this view, the temporary valve is beginning to unfold andexpand. FIGS. 14C and 14D show similar views with the temporary valvesomewhat more deployed;

FIG. 15 depicts a temporary valve of the invention deployed in the aortawith the valve open;

FIG. 16 depicts the temporary valve of FIG. 16 deployed in the aorta,with the valve closed;

FIGS. 17A-17E show various components of a prosthetic valve and fixationsystem in lateral views (left side) and axial views (right side);

FIG. 18 depicts a method of performing surgery on a cardiac valve usinga temporary valve and filter of the invention;

FIG. 19 depicts another method of performing surgery on a cardiac valveusing a temporary valve of the invention;

FIG. 20 depicts the methods of FIGS. 18 and 19 following removal of thecardiac valve and inner cannula;

FIG. 21 depicts deployment of an expandable prosthetic valve through theouter cannula and into the valve annulus, in accordance with theinvention;

FIG. 22 depicts an exemplary method of fixing a prosthetic valve to avessel wall during cardiac rhythm, in accordance with the invention;

FIGS. 23A and 23B depict a method for repairing a stenotic aortic valve,in accordance with the invention;

FIG. 24 depicts another method for performing surgery in a cardiac valveusing a temporary valve and filter in accordance with the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The methods and devices of the present invention can be used forperforming procedures on cardiac valves without cardiac arrest orcardiopulmonary bypass. Various embodiments of the methods and devicesare described to clarify the breadth of the present invention.

Preferred Embodiments—Temporary Filter Device

One critical aspect of any intravascular procedure that potentiallyinvolves the liberation of embolic material is the prevention of strokeand other ischemic events. Below, numerous temporary filter devices aredescribed that allow the passage of procedure instruments into thevascular system while filtering blood passing through the lumen of thevessel into which the instrument is placed.

FIGS. 1A-1F depict multiple stages of deployment of an exemplarytemporary filter device 10 of the present invention. This device isparticularly useful during the manipulation and/or resection of acardiac valve.

FIG. 1A shows the three primary components of the filter device 10-outercannula 1, inner cannula 2, and expandable mesh 3. Outer cannula 1 hasan inner diameter that is greater than the outer diameter of innercannula 2. Mesh 3 is generally tubular when collapsed and at leastconical in part when expanded, and is located on the outside of innercannula 2. The apex of the conical portion of mesh 3 is movably attachedto inner cannula 2 along a length proximal (to the right) of innercannula 2's distal tip. Collapsed mesh 3 is restrained on inner cannula2 between two OD steps 4 rigidly affixed or integral to inner cannula 2.These OD steps may be greater than the generalized outer diameter ofinner cannula 2 or may mark the ends of a reduced diameter section ofinner cannula 2. The apex of mesh 3 is free to slide along and rotateabout inner cannula 2's length between the two OD steps. Expandable mesh3 may be affixed to a ring (not shown) with an inner diameter largerthan the outer diameter of cannula 2 along this length. This allows thecannula to be moved along and rotated about its long axis within atubular vessel without the expandable means and filter material movingagainst and abrading the vessel wall. This feature may act to minimizethe risk of dislodging embolic material from the vessel wall duringmanipulations required by the procedure.

To maintain its collapsed state in the embodiment of FIGS. 1A-1F, theself-expanding, mesh 3 is positioned against the outer surface of innercannula 1. As shown in FIG. 1E (but not shown in FIGS. 1A-1F), a filtermaterial 71, such as woven nylon mesh with a defined pore size, may bepositioned over the mesh 3. Such a material is optional and may be usedto cover at least some portion of expanded mesh 3 and may be placed oneither the outer or inner surface of mesh 3.

The outer and inner cannulae can be constructed from any one of avariety of materials, including, but not limited to, various plastics,rubber, and metals. They can be either wholly rigid or flexible innature. They can be rigid along most of their lengths with a smallflexible region or regions that allow the cannulae to bend. There canfurther be a valve means (not shown) situated along the interior ofinner cannula 2 that prevents the flow of blood while allowing passageof instruments through inner cannula 2. Either or both of inner cannula2 and outer cannula 1 can have additional degassing ports (not shown)exterior to the vascular system to allow removal of air and other gasesfrom the interiors of the cannulae.

Expandable mesh 3 can also be made from any one of a variety ofmaterials, but is preferably constructed from elastic metal woven into atube. This tube preferably has a first diameter in an expanded state anda second, smaller diameter in a compressed state. The first diameter ispreferably similar to that of the aorta or vessel in which the filter isused. The mesh itself can act as a filter or filter material can beattached along its interior or exterior. This embodiment is merely anillustrative example. There are many other potential embodiments of afilter means that could be imagined without departing from the spirit ofthe present invention.

FIG. 1B depicts assembled filter device 10, with the distal end of theinner cannula 2 inserted into the proximal end of the outer cannula 1.

FIG. 1C depicts assembled filter device 10 with the outer cannula Iretracted proximally, exposing mesh 3 and allowing its free to expandagainst the inner wall of the vessel into which it is deployed. In thisembodiment, mesh 3 expands into a conical shape, with the base of thecone extending toward the distal end of the cannulae. Inner cannula 2has a deflected tip that bends the lumen of the cannula away from thelong axis of the device. This bend assists in guiding any proceduralinstrument passed through the lumen of inner cannula 2 toward the wallof the vessel and/or the attachments of a cardiac valve to that wall.The mobility of mesh 3 in this figure permits this bend without alteringthe orientation of mesh 3 relative to the vessel into which it isinserted. As shown, the tip of inner cannula 2 extends beyond mesh 3.Moreover, in some embodiments, that tip is steerable under the remotecontrol of a surgeon. In that configuration, a device, such as valveresecting device which extends out of cannula 2, may be steered toresect desired portion of a stenotic valve, for example. The inventionmay also include a fiber optic viewing assembly extending throughcannula 2.

FIG. 1D depicts the device of FIG. 1C with inner cannula 2 rotated 180°about its long axis and retracted proximally. The sliding attachment ofexpanded mesh 3 to inner cannula 2 allows this to occur without anymotion of mesh 3 relative to the vessel wall.

FIG. 1E depicts the device of FIG. 1D during removal. Outer cannula I isadvanced over inner cannula 2 and is about to compress expanded mesh 3and any entrapped material. The mobility of expanded mesh 3 relative toinner cannula 2 causes mesh 3 to move beyond the distal end of innercannula 2. This ensures that embolic material captured by mesh 3 willnot be trapped between mesh 3 and the exterior of inner cannula 2. Thiswould prevent passage of outer cannula 1 over mesh 3 and inner cannula2. With the mobility of mesh 3 relative to inner cannula 2, a muchgreater amount of embolic material may be trapped compared to a fixedproximal filter as described in the prior art.

FIG. 1F depicts the device of FIG. 1D with filter material 71 added tothe exterior surface of expanded mesh 3. In this embodiment, expandedmesh 3 has been shortened to just the cone portion of the prior meshes.Extending distally beyond this cone are filter extensions 70 that occupyonly a portion of the circumference of a cylinder having a diameterequal to the maximum diameter of the cone-shaped mesh 3. The extensionsare adapted to lie along the vessel wall and rest over the ostium of oneor more arteries that branch from the vessel. The extensionconfiguration of FIG. 1E is advantageous for filtering the ostia ofbranch vessels that may be located between valve commissures, such asthe coronary ostia in the aorta.

For aortic valve applications, extensions 70 are preferably from threepoints spaced around the circumference of the cone's expanded end. Thesepoints are preferably 120 degrees apart. Each extension 70 is preferablya hemi-circular leaflet with the diameter of the hemi-circle beinglocated about the circumference of the cone's base. When deployed;device 10 is oriented so that the base of the cone is expanded towardthe aortic valve. The shape of the three leaflets allows the filter tobe expanded or advanced along the wall of the aorta beyond the planecreated by the three apices of the aortic valve commissures. In thisposition, the leaflets cover and filter the left and right coronaryostia while the filter cone filters blood flowing through the aorta.

In the expanded position, the three extensions 70 can be biased againstthe wall of the aorta by expandable mesh 3, by the stiffness of thefilter material 71, or by the shape of the filter itself. Extensions 70can further be designed to exploit pressure within the vessel tocompress them against the vessel wall.

Such an expandable filter acts to filter just the branch vessels withthe conical portion of the expanded mesh left uncovered by filtermaterial 71. In such an embodiment, either the partial filter extensionscan be employed (as in FIG. 1F) or full cylindrical filters (not shown)that cover the entire circumference of the vessel wall can be employed.

FIGS. 2A, 2B, and 2C show an alternate embodiment of a filter that canbe used to filter emboli from blood flowing through a vessel. Filter 20consists of cannula 17, a valve located within the interior of thecannula (not shown), an expandable means depicted as balloon 19, and afilter depicted as mesh 18. The valve interior to cannula 17 acts toprevent the flow of blood out of the vessel through cannula 17 whileallowing the passage of instruments through the lumen of cannula 17.This valve is positioned to the right of filter 18 as viewed in FIGS. 2Aand 2B. Balloon 19 can be expanded by the injection of gas or liquidthrough port 21. Once inflated, balloon 19 obstructs the flow path ofthe vessel exterior to cannula 17. Hence, the blood must flow into theinterior of cannula 17 and exit the cannula through filter 18. In thisway, emboli are prevented from flowing past the filter. In FIG. 2B, anintravascular instrument 5 has been passed through the inner lumen ofcannula 17. As instrument 5 does not occupy the entire interior flowarea of cannula 17, blood can flow around instrument 5, into cannula 17and through filter 18. FIG. 2C is an end-on view of filter 20 andinstrument 5 from the left side as viewed in FIG. 2B. In this figure,the blood flow path is annulus 22 formed by the inner wall of thecannula 17 and the shaft of the instrument 5. Additional blood flowpaths could be provided through portions of balloon 19. Optionally,these paths additionally have a filter mesh covering the path. Filter 20can be used in a variety of intravascular procedures that would benefitfrom the filtration of blood.

Preferred Embodiment—Combined Temporary Valve Devices

In order to carry out procedures on cardiac valves withoutcardiopulmonary bypass, it is critical to support the function of thevalve during the procedure. Numerous preferred embodiments of temporaryvalves that perform this function are disclosed below. Many of thesevalves are combined with filters to further limit the risk of ischemicevents that might result from liberated embolic material.

FIGS. 3-7 depict one embodiment of such a combined valve and filterdevice. As depicted in FIGS. 3A and 3B, endovascular procedure catheter2′ is inserted into the host. It is positioned over a guide wire 800 atits desired location, for this example in the ascending aorta above thecoronary arteries and below the brachiocephalic artery. Guide wire 800and guiding catheter 700 can then be removed.

Once endovascular procedure catheter 2′ is in position, temporary oneway valve 26, the selectively permeable, filtering membrane 3′, andmounting ring 900 are deployed. Deployment comprises the controlled,adjustable increase in the diameter of valve 26, membrane 3′, and/ormounting ring 900 until they abut or nearly abut the inner wall of thevessel.

Temporary one-way valve mechanism 26 can be comprised of any type of oneway valve. The critical function of valve 26 is to limit the aorticinsufficiency and, thus, the amount of volume overload on the heartgenerated by resecting or manipulating the diseased or damaged hostvalve. This will allow procedures to be performed on the valve andreplacement of the valve without the need for partial or completecardiac bypass or cardiopulmonary bypass.

Next, the host aortic valve is resected, removed or manipulated. If thevalve is to be replaced, the new cardiac valve is implanted. This valvecan be mounted on endovascular procedure catheter 2′ or can be deliveredthrough another port of entry or cannula. Upon completion of theprocedure, all devices are retracted and removed.

The illustrated exemplary endovascular procedure catheter 2′ is acylindrical sleeve that is made of a flexible material. It is durableand resistant to thrombogenesis.

It has several associated components:

-   -   a lumen for the passage of devices e.g. imaging devices, tissue        resecting devices, valve deployment devices, the new valve, or        any other device necessary to perform endovascular procedures on        the endovascular vessels or valves    -   a guiding catheter 700 which is tapered on the end and extends        out of the working port of the endovascular procedure catheter        2′; catheter 700 helps in positioning the endovascular procedure        catheter    -   a one way valve 25 inside the catheter which limits blood loss        during the procedure    -   temporary one way valve 26    -   a selectively permeable, filtering membrane 3′    -   an endovascular mounting ring 900 onto which temporary valve 26        and/or selectively permeable, filtering membrane 3′ are mounted    -   a stent system 950-958 which deploys the mounting ring 900,        temporary endovascular one-way valve 26, and selectively        permeable filtering membrane 3′ by interacting with guiding        catheter 700 and endovascular procedure catheter 2′    -   several holes 600 in the wall of the distal end of the catheter        which may augment antegrade flow of blood during the procedure.

The aforementioned components may be used alone or in combination duringendovascular procedures.

The lumen of endovascular procedure catheter 2′ functions as a workingport allowing for the passage of devices such as imaging devices, tissueresecting devices, or any other device necessary to perform endovascularprocedures on the endovascular vessels or valves.

Endovascular procedure catheter 2′ itself has a one-way valve 25 in itslumen (indicated in phantom) to minimize the loss of fluid i.e. bloodduring the procedure. This one-way valve can be of any configuration aslong as it serves to permit the passage and removal of instrumentsthrough the lumen of the endovascular procedure catheter and inhibitsretrograde blood flow through the endovascular procedure catheter. It islocated proximal to side holes 600 of endovascular procedure catheter2′.

Temporary valve 26 is made of a flexible, durable, non-thrombogenicmaterial. Valve 26 can be any type of one-way valve and consist of asmany or few leaflets as desired as long as it permits the antegrade flowof blood and prevents the retrograde flow of blood. This minimizes thedevelopment of aortic insufficiency created during manipulation of thevalve and minimizes the need for cardiac or cardiopulmonary bypass.Valve 26 depicted in FIG. 3A, 3B and FIG. 4A, 4B is a bileaflet valvemounted on mounting ring 900. It permits antegrade blood flow throughfilter 3′ in the open position and inhibits retrograde blood flow bycollapsing against filter 3′ in the closed position. The valve mechanismis a simple one way, single orifice valve which is mounted on thestabilizer. However, the valve can sit independent of mounting ring 900and as aforementioned can take on any shape as long as it functions as aone way valve.

The center of selectively permeable filtering membrane 3′ is mounted onthe outside wall of endovascular procedure catheter 2′. The relativelylarge diameter peripheral edge is mounted on mounting ring 900. It isconical in shape when deployed and sits just upstream of temporary valve26. Filter membrane 3′ is made of a flexible, durable, non-thrombogenicmaterial that has pores that are sized to permit select fluids through(i.e. blood and blood components) but prevents the flow or embolizationof debris generated during the endovascular procedure. By placing itupstream of temporary valve 26 it prevents prolapse of the temporaryvalve leaflets.

In order to assist in positioning and removal of endovascular procedurecatheter 2′, a tapered guiding catheter 700 of the size of the internaldiameter of endovascular procedure catheter 2′ is placed insideendovascular procedure catheter 2′ as depicted in FIG. 3A. In apreferred form, the tapered end at the distal tip DT extendsapproximately 2 centimeters beyond the distal end of endovascularprocedure catheter 2′, but other-extension lengths may be used. Guidingcatheter 700 is made of flexible material and the end is soft to preventinjury to the vessels during placement of endovascular procedurecatheter 2′. Guiding catheter 700 has a lumen of such a size as topermit its passage over guide wire 800.

Guiding catheter 700 also serves to deploy and retract mounting ring900, temporary valve 26, and filter membrane 3′. FIG. 6 illustrates anexemplary deployment assembly DA for membrane 3′. That assembly DAincludes elements 950-958, described in detail below. As depicted inFIG. 7A, guiding catheter 700 has slots distally which engage extensionarms 955 of struts 952 that support mounting ring 900.

Mounting ring 900 is mounted on the outside of endovascular procedurecatheter 2′ by struts 952. Mounting ring 900 is comprised of a flexible,durable, nonthrombogenic material which abuts the inner lumen of thevessel when deployed. Temporary valve 26 and/or selectively permeablemembrane 3′ are mounted on mounting ring 900. When mounting ring 900 isdeployed so are the mounted components. Mounting ring 900 is deployed ina controlled, adjustable way. Struts 952 are connected to mobile ring953 and fixed ring 950 which is mounted on endovascular, procedurecatheter 2′ as shown in FIG. 6. Mobile ring 953 has extensions 955 whichextend into the lumen of endovascular procedure catheter 2′ by passingthrough slots in the wall of endovascular procedure catheter 2′. Theseextensions are engaged by grooves 957 in the wall of guiding catheter700. Thus as guiding catheter 700 is withdrawn or advanced insideendovascular procedure catheter 2′, mounting ring 900 is deployed orretracted in an umbrella-like manner. Once mounting ring 900 is deployedto the desired diameter, it is “locked” into place by engaging extensionarms 955 into locking slots 958 cut into the wall of endovascularprocedure catheter 2′. At this point, guiding catheter 700 is disengagedfrom extension arms 955 and removed while mounting ring 900 remainsdeployed.

As shown in FIG. 6, the strut mechanism consists of struts 952, rings950 and 953, and hinges 954. The strut mechanism depicted here consistsof three struts 952 that connect mounting ring 900 to the fixed proximalring 950 that is mounted on the outside of procedure catheter 2′. Thesestruts are also connected to support arms 951 which extend to mobiledistal ring 953 also mounted to the outside of endovascularprocedure-catheter 2′. Distal ring 953 has extension arms 955 whichextend through the slots in the wall of procedure catheter 2′ as shownin FIG. 7. Mounting ring 900 is expanded by moving support rings 953 and950 relative to each other. Struts 952 and arms 951 are hinged at pivotpoints 954.

FIGS. 8A and 8B illustrate another embodiment of a combined valve andfilter device for use in intravascular procedures. The filter means ofdevice 40 is the same as device 10 depicted in FIGS. 1A-1E. A temporaryvalve, depicted in FIGS. 8A and 8B as expandable balloon 25, is situatedon the exterior of outer cannula 1′ of the device. A continuous lumen(not shown) extends from the interior of balloon 25 to port 21′. Port21′ is connected to balloon pump 8 by tube 24. FIG. 8A depicts a device40 with filter 3 deployed and balloon 25 deflated during the systolicphase of the cardiac rhythm. FIG. 8B shows balloon 25 in an inflatedstate 25′ during the diastolic phase. Similar to device 10 of FIG. 3,inner cannula 2 may have a lumen through which instruments can be passedto effect an intravascular procedure. In these figures, the filter isshown to the left of the valve. In other embodiments, this relationshipmay be reversed.

FIGS. 9A and 9B show yet another embodiment of a combined valve andfilter device for use in intravascular procedures. Device 50 is the sameas device 10 in FIGS. 1A-1E with the addition of valve means 26 thatcovers the surface of expanded filter 3. In this embodiment, valve means26 consists of one or a number of thin sheets of material that areattached to the exterior of the base of the cone formed by the expandedmesh filter 3. The sheet material is relatively free to move at the apexof the cone such that mesh filter 3 and the sheet material act inconcert as a flap valve. As shown in FIG. 9B, blood flows through filter3 from the interior of the cone causing flap valve 26 to open and allowflow. As shown in FIG. 9A, blood moving toward the exterior of the conecauses the sheet material of flap valve 26 to move against the exteriorof the cone, preventing flow through filter 3. The device can bedelivered with mesh filter 3 and flap valve 26 in a compressed statewithin outer cannula 1 similar to FIG. 3B. Mesh filter 3 and valve 26then expand once outer cannula 1 is retracted. The sheet material canadditionally be affixed to a more proximal segment of inner cannula 2 bythin filaments 27 or the like to aid in returning valve 26 and filter 3to a collapsed state by advancing the outer cannula 1.

FIGS. 10A and 10B show another embodiment of a combined valve and filterdevice. Device 60 is the same as device 10 in FIGS. 1A-1E with theaddition of valve 28 that covers the surface of expanded filter 3. Valve28 consists of a singular sheet of material that covers the entirety ofthe outer surface of the cone portion of expanded mesh filter 3. It isattached, at a minimum, to the cone's base and either its apex or theexterior of inner cannula 2 near the apex. Slit 29 is cut through thesheet between these attachment sites. As shown in FIG. 10A, slot 29closes against filter 3′ during retrograde flow, i.e. flow from thecone's apex toward its base, preventing the passage of blood throughexpanded filter 3. As shown in FIG. 10B, slit 29 moves to an open state29′ during antegrade flow, i.e. from the cone's base toward its apex,allowing passage of blood through expanded filter 3. Slit 29 is shown inthese figures as being in a plane that passes through the long axis ofinner cannula 2, however other orientations are possible. A singularslit is shown, although there could be multiple slits. The sheetmaterial comprising valve 28 can be attached at additional sites alongmesh filter 3 to assist in its function.

FIGS. 11A and 11B depict a combined valve and filter device 30. Thefilter means of device 30 is the same as filter device 20 shown in FIGS.2A-2C. In this embodiment, valve 22 is placed around the exterior ofcannula 17, covering filter 18.

Valve means 22 is preferably a flexible sleeve of material such assilicone rubber. A slit 23 has been cut through the sleeve along itslength. Slit 23 is normally closed, but opens under positive pressurewithin cannula 17. Hence, when this device is placed in the arterialsystem with the distal end (near balloon 19) pointed proximally, slit 23opens during the systolic phase of cardiac rhythm, allowing blood flowthrough filter 18, and closes during the diastolic phase, preventingblood flow through filter 18.

FIG. 11A depicts valve 22 in a closed position. FIG. 11B depicts valvemeans 22 in an open position. Similar to device 20, device 30 may beconfigured with additional flow paths (not shown) passing throughballoon 19. These flow paths may have filters associated with them thatact to filter blood passing therethrough. These flow paths may includeadditional valves that resist retrograde flow while allowing antegradeflow.

Each of the preceding filter and valve embodiments are adapted to beinserted into a vessel through an insertion site and expanded radiallyfrom the center of the vessel at a site remote from that insertion site.

FIGS. 12-14 disclose a temporary valve assembly (with optional filter)100 which can be inserted substantially perpendicular to the long axisof the vessel and expanded at or near the insertion site.

In a preferred form, the valve assembly 100 consists of fourcomponents—a cannula, a deformable loop, a backing element and a valve.In use, the distal end of the cannula is inserted into a vessel, thedeformable loop is then advanced out of the distal end into the vesseland expanded to abut the interior wall of the vessel. The backingelement spans the interior lumen of the expanded loop and is attached tothe loop at at least one point. The backing element is permeable toblood flow. A valve is affixed to either the expanded loop, the backingelement, or both and functions to stop flow along the long axis of thevessel in a first direction through the loop by collapsing against thebacking element and covering substantially all of the lumen formed bythe loop. The valve further allows flow in a second, opposite directionby deflecting away from the backing element during flow through the loopin that direction.

FIG. 12 depicts the detailed construction of the valve device 100 inexploded form. Button 101 is a rigid piece with an opening that is usedto attach it to a central rod 106. Rod 106 is rigid and is attachable tothe valve components of the device (Parts G, A, and B, as illustrated)as well as two small discs 108 and 108′. Secondary button 102 is affixedto valve holder 107 through tube 103. Parts I form proximal seal 104 andare affixed to each other and delivery cannula 105. Tube 103 can slidethrough the lumens of proximal seal 104 and delivery cannula 105. Rod106 can in turn be passed through the lumens of valve holder 107, tube103, and secondary button 102. Proximal seal 104 includes an o-ring thatseals around the exterior of tube 103. Flexible loop 109 has a holethrough the center of its length seen at the base of the loop formed inthe figure. A backing element 110 and valve I 11I are affixed toflexible loop 109 with any suitable fixation means. Backing element 110spans the interior of flexible loop 109. Element 110 is made of flexiblematerial and in its preferred embodiment is a woven nylon sheet. Thissheet can act to filter particulate debris from blood passing throughflexible loop 109. Valve 111 is a set of valve leaflets. In this figurethere are six valve leaflets. These leaflets are attached to theperiphery of backing means 110, flexible loop 109 or both, for example,by way of a ring of material surrounding the leaflets. Once assembled,backing element 110, valve 111, and flexible loop 109 are affixed tovalve holder 107 through the two small through-holes in valve holder107. These through holes act as hinge points about which the ends offlexible loop 109 can pivot. Rod 106 is inserted through a central lumenin valve holder 107, superior disc 108, the hole in flexible loop 109,and finally inferior disc 108′. Discs 108 and 108′ are affixed to rod106 to immobilize the center section of flexible loop 109 relative tothe lower end of rod 106. Valve holder 107 fits within the lumen ofdelivery cannula 105.

In a preferred embodiment of this valve assembly 100, backing element110 is a porous sheet of material that further acts to filter bloodpassing through deformable loop 109. This porous sheet can be a wovenmaterial with an open area that allows the passage of blood, althoughother forms may be used, all within the scope of the invention.

In another preferred implementation of the device 100, deformable loop109 is made from a strip of material with a non-circular cross section.It may have a rectangular cross-section. The thicker side of therectangle can be positioned against the wall of the vessel. This givesthe loop greater flexibility to conform easily to the shape of the walland greater stiffness against flopping or twisting away from the vesselwall under the pressure of blood flowing through the vessel.

The valve 111 is preferably effected by a set of valve leaflets asshown. The valve leaflets can collapse, in an overlapping manner,against backing element 110 to prevent flow in a first direction throughthe loop 100. The leaflets may alternatively coapt against each other soas to prevent flow in the first direction. In the latter form, thedevice may be used without a filter (backing element), to provide avalve-only device. Generally, such a device would be used with a filterin another location.

The leaflets of valve 111 are preferably formed from thin, flexiblesheets of material. There may be any number of leaflets. The leafletsmay be sized to act in concert to close the flow path formed by theloop. The leaflets may alternatively be oversized, such that fewer thanall of the leaflets are required to close the flow path.

In one embodiment, there may be two or more leaflets with one or somecombination of the leaflets capable of closing the flow path through theloop against flow in the second direction.

The valve 111 may alternatively be a sheet of material cut with slits.The slits stay substantially closed (not parted) to prevent flow in afirst direction through the flow path created by the loop 109 bycollapsing against the backing element. The slits allow the passage ofblood in the second, opposite direction through the flow path by partingopen in the direction away from the backing element.

In a preferred method of using a valve of the form of FIGS. 12-14, thedevice is expanded from a point or set of points on the circumference ofthe vessel into which it is placed until the valve occupiessubstantially all of the cross sectional flow area of that vessel.

Another method of using that device of the form of FIGS. 12-14, is toinsert the distal end of the device into the vessel through an entrysite and expanding the valve proximate to the entry site. This allowsthe device to be placed easily, near the heart, during an open-chestprocedure.

Another method of using the device is to insert its distal end into avessel along a path that is substantially perpendicular to the long axisof the vessel and expand the valve about that path. In a preferredapplication of this method, the device is expanded until it occupies theentire flow path of the vessel and sits within a cross-section of thatvessel taken perpendicular to the vessel's long axis. This minimizes thelength of the vessel taken up by the temporary valve device.

FIG. 15 depicts temporary valve assembly 100, with its valve deployed inaorta 215. In this figure, a procedure is indicated as being performedon aortic valve 212 through a separate access cannula 201 usingprocedure instrument 205. Device 100 is shown with its valve open (as inFIG. 13C′) allowing flow through flexible loop 109. This figure depictsthe systolic phase of cardiac rhythm.

In FIG. 16, valve assembly 100 is similarly positioned, but is closed(as in FIG. 13D′), preventing flow back toward the heart. This figuredepicts the diastolic phase of cardiac rhythm. The position of valveassembly 100 distal to the three branches from the aortic arch is shownas a representative application of the device and by no means limits itsapplication to this position.

Preferred Embodiment—Prosthetic Valve

Another aspect 6f the present invention is a valve fixation device,illustrated in FIGS. 17A-17E. The valve fixation device 300 is used tosecure a prosthetic valve to the wall of a vessel. In a preferredembodiment, the prosthetic valve is a stentless tissue valve. The tissuevalve has a base, located proximal to the heart when placed in ananatomic position, and an apex located distal to the base. Theprosthetic valve preferably has three commissures and three leaflets.The apex of the commissures is toward the apex of the valve. The valvehas an interior surface and an exterior surface. The interior surfaceserves as an attachment site for the valve leaflets to the valve anulus.The exterior of the valve is generally smooth and forms at least aportion of a cylinder. The valve has a long axis that runs along thelong axis of the cylinder.

The valve fixation device consists of at least one substantially rigidstrut and at least two expandable fixation rings. The strut(s) runsalong the exterior surface of the valve in a direction substantiallyparallel to the long axis of the valve. The rings are preferably locatedabout the circumference of the base and apex of the valve. These ringsare affixed to the strut(s) such that the distance along the long axisof the valve between the rings is fixed. The rings may be located eitheron the interior or exterior surface of the valve. The valve ispreferably affixed to both the rings and the struts by any suitablefixation means including, but not limited to barbs, sutures, staples,adhesives, or the like. In a preferred embodiment, the valve fixationdevice 90 has three struts 92 and two rings 91. Each of the three struts92 is affixed to the valve along an axis that is parallel to the longaxis of the valve and passes proximate to one of the valve commissures.

The rings 91 are preferably self-expanding. Alternatively, rings 91 maybe plastically expandable by any suitable means, such as a balloon. Therings 91 and/or strut(s) 92 may employ barbs or spikes 83 at anylocation along their exterior to aid in securing the valve to the vesselwall. The rings 91 may further be affixed to the exterior of the valveand employ a sealing material 84 or other means, on rings 91, to aid insealing rings 91 against the vessel wall.

In the preferred embodiment, the valve fixation device 90 and attachedtissue valve 80 are inserted in a compressed state into the vascularsystem. The compressed valve/fixation system is then advanced to thesite of implantation, expanded, and secured to the vessel wall. Whenused as an aortic valve replacement, the compressed valve/fixationsystem can be inserted through any peripheral artery distal to theaorta.

Alternatively, the valve can be inserted through the wall of a cardiacchamber or directly into the aorta itself. Various devices can beemployed to aid in delivering the valve to the implantation site,including, but not limited to delivery cannulae, catheters, and any of avariety of valve holders known in the art.

FIG. 17A depicts a stentless tissue valve 80 such as those known in theart.

The valve consists of valve wall 81 and three attached leaflets 82.Valve wall 81 has three sections of its cylindrical form removed so asnot to block branch vessels such as the coronaries. There are manyvariations of this type of valve prosthesis. Any flexible valve with awall and leaflets can be used with the present invention.

FIG. 17B depicts valve fixation device 90 of the present invention. Thisembodiment comprises two expandable rings-like structures 91, shown intheir expanded state, and three struts 92. Struts 92 are relativelyrigid and do not change dimensions from the compressed to the expandedstate of the device 90. The three struts 92 are separated by roughly 120degrees in the illustrated form, as shown in the axial view of thefigure, corresponding to the three commissures of the prosthetic valve.Struts 92 are preferably relatively rigidly attached to expandable rings91 such that the two expandable rings 91 may not rotate about theircentral axes relative to each other. This avoids twisting of tissuevalve 80 during deployment, minimizing the risk of valve leakage.

FIG. 17C depicts valve fixation device 90 affixed to tissue valve 80,forming valve assembly 85. Fixation device 90 can be affixed to tissuevalve 80 at sites along struts 92, expandable rings 91, or both. In thisembodiment, struts 92 and expandable rings 91 are affixed to the outsideof the valve wall 81.

FIG. 17D depicts the assembly 85 of FIG. 17C in a compressed state 85′suitable for insertion into an artery or vein through a relative smalleropening.

FIG. 17E depicts another embodiment of the valve fixation device 90. Inembodiment 86, barbs 83 reside on the exterior surfaces of both struts92 and expandable rings 91 to aid in securing the device 90 to a vesselwall. Felt 84 has also been added to the expandable rings 91 to aid insealing against peri-valvular leaks. Felt 84 could be added to struts92. Other forms of sealant may be used as well.

Preferred Embodiments—Procedure Methods

The above embodiments may be used alone or in combination with otherdevices to carry out procedures on a cardiac valve while the heart isbeating. Below are numerous such procedure methods in accordance withthe invention, which are described to clarify the breadth of possibleapplications of these preferred device embodiments.

FIG. 18 depicts a procedure being carried out on aortic valve 412 whilethe heart is beating. Instrument 405 is manipulating aortic valve 412following the placement of both temporary valve 406 and filter device410. In this embodiment, temporary valve 406 and filter device 401 (forexample device 10 of FIGS. 1A-1F) are separate instruments that havebeen inserted directly into the aorta through separate insertion sites414 and 413. Alternatively, valve 406 and filter 410 may be effected ina single instrument placed through a single incision. Valve 406 andfilter 410 may also be inserted from a peripheral vessel and advanced toa location within the aorta.

Mesh filter 403 is deployed through outer cannula 401 to a preferredsite proximal to the brachiocephalic artery 411. In this position,filter 403 prevents distal embolization of debris that may be dislodgedduring manipulation of valve 412. Portions of inner and outer cannulae401 and 402 and instrument 405 extend to the exterior of the aorta wherethey can be manipulated by a surgeon. In the method illustrated by FIG.18, balloon valve 406 is deployed in the descending aorta 415. Balloon406 is inflated and deflated by an attached balloon pump 408 exterior tothe patient. Balloon pump 408 is in fluid connection with balloon 406through tube 407. Balloon pump 408 is timed to the cardiac rhythm sothat it inflates balloon 406 during substantially all of the diastolicphase and deflates balloon 406 during substantially all of the systolicphase. This allows the valve 406 to perform the function of aortic valve412 while the aortic valve is manipulated.

FIGS. 19, 20, and 21 show another form of the present invention. Thosefigures depict sequential views of method of removing the native aorticvalve and replacing it with a permanent prosthetic valve while the heartis beating. In FIG. 19, balloon valve 406 has been placed in thedescending aorta 415. Cannula 401 has been placed into the aorta toallow the passage of instrument 405. Cannula 401 may have a valve (notshown) along its interior that acts to prevent the flow of blood throughthe cannula while allowing the passage of various instruments.Instrument 405 has been inserted through cannula 401 to remove nativeaortic valve 412. FIG. 20 shows the embodiment described in FIG. 19after substantially all of the aortic valve has been removed. Portions412′ of the aortic valve may remain without deviating from the scope ofthis invention. Indeed resection of native valve 412 can be limited toremoval of those portions of the right and left valve leaflets thatwould cover coronary arteries 409 if the valve were to be compressedagainst the inner walls of the aorta.

Instrument 405 has been withdrawn from outer cannula 401 to allow theinsertion of valve prosthesis 416 into the aorta. In this figure,temporary valve 406 is performing the full function of the resectedaortic valve. FIG. 21 shows valve prosthesis 416 expanded against andaffixed to the aortic wall at a site near the previous attachment of thenative valve. Once valve prosthesis 416 is in place and functioning,temporary valve 406 can be removed. No filter is shown in FIGS. 19, 20,and 21. A filter is not necessary for completing the procedure, butcould be used without deviating from the intent of the presentinvention.

Another method of replacing a cardiac valve while the heart is beating,employs described using a combination of the methods disclosed in FIGS.18, 20, and 21. In accordance with the latter method, a set of twoconcentric cannulae, inner cannula 402 that fits within the lumen ofouter cannula 401, are inserted into the vessel. The method furtherinvolves the steps of advancing the set of cannulae to a site downstreamof the cardiac valve, expanding an expandable member 403 from theexterior of the inner cannula 402, performing a procedure at least inpart through the lumen of the inner cannula that removes or disruptscardiac valve 412, retracting inner cannula 402 and expandable member403 through the inner lumen of outer cannula 401, leaving the distal endof outer cannula 401 near the annulus of cardiac valve 412, inserting acompressed valve prosthesis 416 through the inner lumen of outer cannula401 to the site of the cardiac valve anulus, and expanding and affixingprosthetic valve 416 to the cardiac valve annulus. Using the set of twocannulae allows the insertion-and removal of-expandable member 403 onthe exterior of inner cannula 402 as well as valve prosthesis 416 andother instruments through the lumen of outer cannula 401 without losingthe position of outer cannula 401 relative to the cardiac valve duringthe procedure. Expandable member 403 is located anywhere along thelength of inner cannula 402 and performs any number of functions such asacting as a temporary valve, acting as a filter, or removing ordisrupting the cardiac valve leaflets.

FIG. 22 depicts one method of fixing a prosthetic valve 516 to a vesselwall during cardiac rhythm. In this embodiment, prosthetic valve 516 isinserted into aorta 515 in a compressed state through access cannula501. Prosthetic valve 516 is then expanded to abut the inner wall ofaorta 515. A needle 512 and suture 514 are then passed from the outersurface of aorta 515 through the aortic wall and into the prostheticvalve 516. In this depiction, three sutures are used to tack prostheticvalve 516 to the aortic wall in locations superior to the valvecommissures. Alternatively, a fixation means can be passed from theinterior wall of aorta 515 through to the exterior surface. The fixationmeans can be a staple, suture or other suitable means.

In accordance with another aspect of the present invention, a compressedprosthetic valve is inserted into a vessel downstream of the cardiacvalve to be replaced. The prosthetic valve is then expanded to allow itto function temporarily in its downstream location. With that valvetemporarily placed, and functioning, a procedure on the cardiac valve isperformed, involving the disruption and/or removal of the cardiac valve.Then the prosthetic valve is advanced toward the site of the excised ordisrupted cardiac valve, and affixed at a site within the vessel at ornear the site of the excised or disrupted cardiac valve. During theprocedure on the cardiac valve, the expanded prosthetic valve functionsas the native valve, preventing retrograde flow.

The cardiac valve procedure occurring while the prosthetic valve isdownstream of its final position, may be performed through an incisionsomewhere between the cardiac valve and the prosthetic valve.Alternatively, the procedure could be done with tools inserted throughthe functioning prosthetic.

FIGS. 23A and 23B depict a method for repairing a stenotic aortic valvein accordance with the invention. FIG. 23A shows stenotic aortic valve612 within the aortic root. View 1 in this figure shows two views ofstenotic valve 612 looking along the long axis of aorta 615 proximal tothe valve. In this view, the leaflets of valve 612 provide a reducedaperture due to the stenosis.

FIG. 23B shows the aortic valve after the repair method of the inventionhas been implemented. Initially, the aortic valve 612″ is disrupted byincising each leaflet such that six leaflets are formed. A balloonvalvuloplasty may optionally be performed on valve 612″. Following thedisruption of valve 612″, a valve support 620 is positioned upstream ofthe valve 612″. Preferably, the valve support 620 includes an expandableouter ring (circular or otherwise, eg elliptical, oval, polygonal),which is spanned by a bloodflow permeable structure. The outer ring isexpanded to be proximal to and affixed to the aortic wall, so that thesupport structure provides a surface against which the disruptedleaflets can collapse, forming a multileafed flap valve, similar to thevalve described above in conjunction with FIGS. 12-14.

FIG. 24 depicts a procedure being performed on the aortic valve 412while the heart is beating. Instrument 405 is manipulating aortic valve412 following the placement of both temporary valve 100 and filterdevice 410 (for example, device 10 of FIG. 1F). In this embodiment,temporary valve 100 and filter device 410 have been inserted directlyinto the aorta through separate insertion sites 414 and 413.

Mesh filter (not visible) has been deployed through outer cannula 401 toa site proximal to the coronary arteries 409. Filter material 71 coversthe mesh filter. Filter extensions 70 extend from the filter materialand form filter leaflets that prevent embolic material from entering thecoronary arteries 409. Portions of the inner and outer cannulae 401 and402 and instruments 405 extend to the exterior of the aorta where theycan be manipulated by the surgeon.

In the method illustrated in FIG. 24, temporary valve 100 is deployed inthe descending aorta 415, and as described earlier, expands to occupythe entire flow path. Temporary valve 100 is shown in the systolic phaseof cardiac rhythm, i.e. with its valve open (as in FIG. 13D′), allowingflow through the device.

In other embodiments of the invention the temporary valve and/or filtermay be deployed downstream of the aortic valve, or in still other forms,downstream of the mitral or other cardiac valves. Further, these devicesmay be deployed downstream of one cardiac valve while procedures arebeing performed on another cardiac valve upstream of the devices.

Although preferred and other embodiments of the invention are describedherein, further embodiments may be perceived by those skilled in the artwithout departing from the scope of the claims.

1. A method for enabling performance of an operation on a cardiac valveof a heart while the heart is beating, comprising the steps of: a)placing at least one temporary valve in a flow path of a blood vesseldownstream from said cardiac valve, said temporary valve being operativeto effect greater antegrade flow than retrograde flow through saidvessel; and b) placing at least one temporary filter in said flowpathdownstream from said cardiac valve, said filter being operative torestrict the passage of emboli while allowing blood to flow through saidvessel.
 2. A method for performing an operation on a cardiac valve of aheart while the heart is beating, comprising the steps of: a)positioning at least one temporary valve in a flow path of a bloodvessel downstream from said cardiac valve, said temporary valve beingoperative to effect greater antegrade flow than retrograde flow throughsaid vessel; b) resecting at least a portion of the cardiac valve; andc) affixing at least one prosthetic valve at or downstream from saidresected cardiac valve.
 3. A device for performing intravascularprocedures wherein at least a portion of the device is adapted forplacement in a flowpath of a blood vessel, said intravascular portioncomprising: a) a valve means that acts to allow greater antegrade flowthan retrograde flow through said vessel; and b) a filter operative torestrict the passage of emboli while allowing blood flow through saidvessel.
 4. A device for filtering blood flowing through a vessel withinthe vascular system, said device comprising: a) an expandable elementoperative to direct bloodflow through said vessel to a flow area of saidvessel; and b) a filter operative to filter the blood passing throughsaid portion of said flow area.
 5. A device for use in intravascularprocedures, wherein at least a portion of the device is adapted forplacement in a flowpath of a blood vessel, the intravascular portioncomprising: a) a filter including a flowpath spanning portion operativeto filter at least a portion of blood flowing through said vessel; andb) a valve assembly including valve elements and said flowpath spanningportion, said valve elements being positionable in a first state awayfrom said flowpath spanning portion to permit antegrade blood flowthrough said flowpath spanning portion, and positionable in a secondstate adjacent to said flowpath spanning portion to prevent retrogradeblood flow through said flowpath spanning portion.
 6. An expandablevalve for insertion into a vessel to allow greater flow along a centralaxis of said vessel in a first direction than in a second, oppositedirection, said valve comprising: a) an expandable member adapted forselective expansion to abut the wall of the vessel, said expandablemember having at least one flow path therethrough; b) a valve element,said valve element opening during flow through said flow path in saidfirst direction while closing over said flow path during flow in saidsecond direction; and wherein said expandable member and said valveelement are unitary assembly adapted for insertion into said vessel in acollapsed state along an axis angularly offset from said central axis ofsaid vessel.
 7. An expandable valve adapted to be expanded to abut theinterior wall of a vessel and occupy substantially all of across-sectional flow area of said vessel, said valve comprising: a) aflexible, elongated element, said elongated element configured into aloop that can be collapsed to form two adjacent parallel segmentsmutually joined at their respective ends, and that can be expanded to aring-like form adapted to abut the interior wall of said vessel, saidloop adapted to occupy a portion of the cross-sectional flow area ofsaid vessel; b) a backing element affixed to and spanning said loop,said loop and said backing elements forming a valve base; and c) atleast one valve leaflet peripherally affixed to said valve base, saidvalve leaflet adapted in a first state to collapse against said backingelement to prevent flow in a first direction through said valve base,and adapted in a second state to move away from said backing element topermit fluid flow in a second direction through said valve base.
 8. Anexpandable valve according to claim 7 having at least four valveleaflets.
 9. An expandable valve according to claim 7 having at leasttwo valve leaflets affixed to said valve base, said valve leaflets sizedsuch that a combination of fewer than the total number of said valveleaflets can resist flow in a first direction through said valve baseand open to allow flow in a second direction through said valve base.10. A method for providing a valve within a tubular vascular structure,comprising: a) inserting an expandable valve in a collapsed state intosaid vascular structure through an entry site; and b) expanding saidvalve within said vascular structure to an expanded state proximate tosaid entry site.
 11. A method according to claim 10 wherein said valveis inserted into said vascular structure along an axis transverse to acentral axis of said vascular structure.
 12. An expandable intravascularfilter device adapted to filter blood flowing through a tubular vascularstructure, said filter comprising: a) an elongated filament, saidfilament having a proximal and a distal end, said distal end beingadapted to be inserted into said vessel through an entry site; and b) anexpandable filter, said filter being adapted to track along saidfilament, said filter having a collapsed state with a relatively smallmaximum transverse dimension and having an expanded state with arelatively large transverse dimension, said filter being insertable intosaid vessel in a collapsed state and expandable in said vessel to anexpanded state, wherein said filter occupies a cross sectional flow areaof said vessel not occupied by said filament, said filter being attachedto said filament proximal to the distal end of said filament.
 13. Anexpandable intravascular filter kit, said kit comprising: a) anelongated cannula having an outer diameter D and defining at least onelumen passing therethrough, said cannula having a proximal and a distalend, said distal end being adapted for insertion into a blood vesselthrough an entry site, b) a filter axially and slidingly positionedalong a limited portion of the outer surface of said cannula near saiddistal end, said filter being collapsible in a first state whereby amaximum dimension of said filter and said cannula is relatively small,and thereby being adapted in said first state for insertion into saidvessel and being expandable in a second state, whereby said filterextends transverse to a central axis of said cannula, thereby beingadapted to span at least a portion of said vessel and to filter bloodflowing therethrough.
 14. An expandable intravascular filter accordingto claim 13 wherein said filter is circumferentially slidinglypositioned on said limited portion.
 15. An expandable intravascularfilter according to claim 12 wherein said filter includes at least oneof circumferentially extending filter elements extending from a distalend thereof, said circumferentially extending filter elements beingadapted to filter blood passing therethrough along an axis transverse toa central axis of said cannula.
 16. An expandable intravascular filterdevice according to claim 12 wherein said distal end of said cannula isselectively deflectable away from a central axis of said cannula.
 17. Avalve fixation device for affixing a flexible prosthetic valve to theinterior wall of a vessel, said prosthetic valve having a generallycylindrical shape with a base, an apex, an interior surface and anexterior surface, said prosthetic valve further having a long axispassing through the centers of the circles formed by at least twocircumferences of said cylindrical shape along the distance between saidapex and said base, said fixation device comprising: a) at least twoexpandable fixation rings, said rings being expandable from a firstcompressed state having a relatively small maximum transverse dimensionto a second expanded state having a relatively large maximum transversedimension, said rings expandable in a direction perpendicular to thelong axis of said prosthetic valve, each of said rings being affixed tosaid prosthetic valve near a respective end thereof.
 18. A valvefixation device according to claim 17 further comprising at least onerigid strut on the exterior surface of said prosthetic valve passingalong an axis parallel to the long axis of said valve, said struts beingaffixed to said rings at least one point on each of said rings.
 19. Aprosthetic cardiac valve comprising: a) flexible prosthetic valve meanshaving a generally cylindrical shape with a base, an apex, an interiorsurface and an exterior surface, said prosthetic valve further havingvalve leaflets joined to said interior surface, said leaflets formingcommissures where two of said leaflets meet along said interior surface,said prosthetic valve further having a long axis passing through thecenters of the circles formed by at least two circumferences of saidcylindrical shape taken along the distance between said apex and saidbase; b) at least two expandable fixation rings, each being affixed to arespective end of said prosthetic valve at least one point, said ringsbeing expandable in a direction perpendicular to the long axis of saidprosthetic valve; and c) at least one rigid strut on the exteriorsurface of said prosthetic valve passing along an axis parallel to thelong axis of said valve, said struts being affixed to said rings atleast one point on each of said rings.
 20. A prosthetic cardiac valveaccording to claim 19 comprising two expandable fixation rings and threerigid struts, each of said struts passing proximate to one of saidcommissures.
 21. A prosthetic cardiac valve according to claim 20wherein said struts are affixed to said prosthetic valve at least onepoint.
 22. A prosthetic cardiac valve according to claim 20 wherein saidrings are affixed to the exterior surface of said prosthetic valve. 23.A prosthetic cardiac valve according to claim 20 wherein said rings arefurther affixed to a sealing means for sealing against an interiorsurface of said vessel wall.
 24. A prosthetic cardiac valve according toclaim 20 wherein said struts are further affixed to a sealing means forsealing against the interior surface of said vessel wall.
 25. Aprosthetic cardiac valve according to claim 20 wherein said rings haveintegral fixation means for securing said prosthetic valve to aninterior surface of said vessel wall.
 26. A prosthetic cardiac valveaccording to claim 20 wherein said struts have integral fixation meansfor securing said prosthetic valve to the interior surface of saidvessel wall.
 27. A method for affixing a prosthetic valve to the wall ofa vessel, comprising the steps of: a) during cardiac rhythm, insertingsaid prosthetic valve into a vessel in a compressed state; b) advancingsaid prosthetic valve to the site of implantation; c) expanding saidprosthetic valve to an expanded state; and d) passing at least onefixation means entirely through the wall of said vessel.
 28. The methodof claim 27 wherein said fixation means is passed from the inside ofsaid vessel through to the outside of said vessel.
 29. The method ofclaim 27 wherein said fixation means is passed from the outside of saidvessel through to the inside of said vessel.
 30. The method of claim 27wherein said fixation means is a suture.
 31. The method claim 27 whereinsaid method is performed during cardiac rhythm.
 32. A method ofreplacing a native cardiac valve, comprising the steps of: a) duringcardiac rhythm, inserting into a vessel the distal ends of a set of twoconcentric cannulae including an inner cannula and an outer cannula,said inner cannula having a smaller outer diameter than the innerdiameter of said outer cannula such that said inner cannula can beslidably placed within a lumen of said outer cannula; b) advancing thedistal ends of said cannulae to a site proximate to said cardiac valve;c) positioning said cannula whereby the distal end of said inner cannulaextends beyond the distal of end of said outer cannula, and expanding anexpandable member secured to an outer surface of said cannula, wherebysaid expandable member occupies substantially all of the cross sectionalflow area of said vessel; d) performing a procedure on said native valveat least in part through a lumen of the inner cannula; e) removing saidinner cannula and said expandable member through said lumen of saidouter cannula, the distal end of said outer cannula remaining proximateto the attachment site of said cardiac valve to said vessel; f)advancing a valve prosthesis through said outer lumen of said cannula toa site at or near the attachment site of said cardiac valve; and g)affixing said valve prosthesis to the wall of said vessel.
 33. A methodof repairing and replacing a stenosed cardiac valve comprising the stepsof: a) during cardiac rhythm, disrupting said cardiac valve, withoutcompletely removing said cardiac valve such that said cardiac valve nolonger functions as a valve, thereby decreasing pressure drop acrosssaid cardiac valve; and b) implanting a prosthetic valve downstream ofsaid cardiac valve.
 34. A method of replacing a diseased cardiac valvecomprising the sequential steps of: a) during cardiac rhythm, placing avalve prosthesis into a vessel downstream of said cardiac valve; and b)resecting at least some portion of said cardiac valve.
 35. A method ofreplacing a diseased cardiac valve comprising the sequential steps of:a) during cardiac rhythm, placing a valve prosthesis into a vesseldownstream of said cardiac valve; b) resecting at least some portion ofsaid cardiac valve; c) repositioning said valve prosthesis to or nearthe site of the resected cardiac valve; and d) affixing said valveprosthesis to the wall of said vessel.
 36. A method of replacing adiseased cardiac valve comprising the steps of: a) during cardiacrhythm, inserting an expandable valve prosthesis into a vessel ina-collapsed state and positioning said valve prosthesis at the site ofsaid cardiac valve; b) expanding said valve prosthesis and crushing saidcardiac valve against the wall of said vessel; and c) affixing the valveprosthesis to said vessel wall through the crushed cardiac valve.
 37. Amethod of resecting cardiac valve leaflets attached to the inner wall ofa vessel comprising the steps of: a) during cardiac rhythm, insertingone end of a elongated resection instrument into the vascular system andadvancing said end proximate to said cardiac valve; b) directing saidend against the wall of said vessel; c) advancing said end along thewall of said vessel until it makes contact with a the attachment of saidleaflet of said cardiac valve to said vessel; and d) resecting saidleaflet with said resection instrument.
 38. A method of repairing astenotic cardiac valve comprising the steps of: a) : during cardiacrhythm, disrupting the leaflets of said valve such that the pressuredrop across said valve is decreased; and b) supporting said leafletswith a valve support device that at least in part spans the flow area ofsaid valve upstream of said valve leaflets.